Hu Dongzhi, McPheeters Claiborne Co, Yu Edward T, Schaadt Daniel M
Institut für Angewandte Physik/DFG-Center for Functional Nanostructures, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
Nanoscale Res Lett. 2011 Jan 12;6(1):83. doi: 10.1186/1556-276X-6-83.
A new measure to enhance the performance of InAs quantum dot solar cell is proposed and measured. One monolayer AlAs is deposited on top of InAs quantum dots (QDs) in multistack solar cells. The devices were fabricated by molecular beam epitaxy. In situ annealing was intended to tune the QD density. A set of four samples were compared: InAs QDs without in situ annealing with and without AlAs cap layer and InAs QDs in situ annealed with and without AlAs cap layer. Atomic force microscopy measurements show that when in situ annealing of QDs without AlAs capping layers is investigated, holes and dashes are present on the device surface, while capping with one monolayer AlAs improves the device surface. On unannealed samples, capping the QDs with one monolayer of AlAs improves the spectral response, the open-circuit voltage and the fill factor. On annealed samples, capping has little effect on the spectral response but reduces the short-circuit current, while increasing the open-circuit voltage, the fill factor and power conversion efficiency.
提出并测量了一种提高铟砷量子点太阳能电池性能的新方法。在多叠层太阳能电池的铟砷量子点（QD）顶部沉积一层单层砷化铝。这些器件通过分子束外延制造。原位退火旨在调整量子点密度。比较了一组四个样品：有无砷化铝帽层的未进行原位退火的铟砷量子点以及有无砷化铝帽层的原位退火铟砷量子点。原子力显微镜测量表明，在研究无砷化铝覆盖层的量子点原位退火时，器件表面存在孔洞和虚线，而用一层单层砷化铝覆盖可改善器件表面。在未退火的样品上，用一层单层砷化铝覆盖量子点可改善光谱响应、开路电压和填充因子。在退火样品上，覆盖对光谱响应影响不大，但会降低短路电流，同时增加开路电压、填充因子和功率转换效率。
